Hierarchical Style Modeling: A generative framework for Style-Centric Generation of 3D Models

This work focuses on incorporating style - specifically visual style - into procedural content generation processes. Specifically, I model style as a series of constraints that must be satisfied while an object is generated

Environmental impact analysis of alternative pallet management systems

Pallets, the most common unit-load platform, allow the transportation of goods in an efficient and reliable way. Every year, 700 million new pallets are manufactured and become part of the approximately 2 billion pallets that are in circulation in the U.S. The total life-cycle environmental impact of pallets depends on materials, manufacturing, handling processes, and the disposal practice (end-of-life). Plastic pallets can be lighter and might last longer but their manufacturing processes are energy intensive and could contribute significantly to greenhouse gas (GHG) emissions. On the other hand, wooden pallets can be cheaper and easily repaired but present a shorter life. The ability to control the end-of-life of the pallets and the associated environmental impacts of each scenario allows pallet pooling service companies to provide logistics arrangements that are attractive to those companies seeking to better manage their carbon footprint. The appropriate choice of pallet type (i.e. material, durability, etc.) and management structure (e.g. cost, lease vs. buy, etc.) may lead to a more sustainable logistics operation. The purpose of this study is to provide a model that would determine the impact of pallet materials, manufacturing, distribution, and take back operations on an environmental performance metric (such as carbon dioxide emissions) as well as cost. Mixed integer programming (a minimum cost multi-commodity network flow problem) is used to design the system that determines the mix of pallets (type, quantity, and pallet management system) for product distribution that balances overall environmental impacts and costs according to companies\u27 needs. Such a tool would aid in decision making at the logistics and distribution levels. Results from a case study of a large grocery distributor/retailer in the Northeast is presented

X-Risk Analysis for AI Research

Artificial intelligence (AI) has the potential to greatly improve society, but as with any powerful technology, it comes with heightened risks and responsibilities. Current AI research lacks a systematic discussion of how to manage long-tail risks from AI systems, including speculative long-term risks. Keeping in mind the potential benefits of AI, there is some concern that building ever more intelligent and powerful AI systems could eventually result in systems that are more powerful than us; some say this is like playing with fire and speculate that this could create existential risks (x-risks). To add precision and ground these discussions, we provide a guide for how to analyze AI x-risk, which consists of three parts: First, we review how systems can be made safer today, drawing on time-tested concepts from hazard analysis and systems safety that have been designed to steer large processes in safer directions. Next, we discuss strategies for having long-term impacts on the safety of future systems. Finally, we discuss a crucial concept in making AI systems safer by improving the balance between safety and general capabilities. We hope this document and the presented concepts and tools serve as a useful guide for understanding how to analyze AI x-risk

An Overview of Catastrophic AI Risks

Rapid advancements in artificial intelligence (AI) have sparked growing concerns among experts, policymakers, and world leaders regarding the potential for increasingly advanced AI systems to pose catastrophic risks. Although numerous risks have been detailed separately, there is a pressing need for a systematic discussion and illustration of the potential dangers to better inform efforts to mitigate them. This paper provides an overview of the main sources of catastrophic AI risks, which we organize into four categories: malicious use, in which individuals or groups intentionally use AIs to cause harm; AI race, in which competitive environments compel actors to deploy unsafe AIs or cede control to AIs; organizational risks, highlighting how human factors and complex systems can increase the chances of catastrophic accidents; and rogue AIs, describing the inherent difficulty in controlling agents far more intelligent than humans. For each category of risk, we describe specific hazards, present illustrative stories, envision ideal scenarios, and propose practical suggestions for mitigating these dangers. Our goal is to foster a comprehensive understanding of these risks and inspire collective and proactive efforts to ensure that AIs are developed and deployed in a safe manner. Ultimately, we hope this will allow us to realize the benefits of this powerful technology while minimizing the potential for catastrophic outcomes

Dobutamine stress echocardiography for detection and assessment of coronary artery disease

AbstractStress echocardiography with dobutamine infusion for detection of coronary artery disease is a potential alternative to exercise stress testing with some theoretic advantages. Fifty patients who were not receiving cardioactive medication were prospectively studied with two-dimensional echocardiography and 12-lead electrocardiography (ECG) during incremental dobutamine infusion (5, 10, 15 and 20 μg/kg body weight per min, each dose for 8 min). Images were analyzed by using an 11-segment left ventricular model. All patients underwent correlative exercise ECG and coronary angiography, which revealed normal coronary arteries in 14 and significant disease (≥70% diameter stenosis) in 36.Peak rate-pressure product during dobutamine infusion was 18,845 ± 4,156 versus 23,740 ± 6,158 mm Hg/min on exercise (p < 0.01). Interobserver concordance for wall motion analysis was good (kappa coefficient = 0.77). The use of baseline (n = 14) or reversible (n = 24) regional asynergy to define an abnormal dobutamine echocardiogram resulted in a sensitivity for detecting coronary artery disease of 78% and a specificity of 93%. Corresponding data for the dobutamine ECG were 47% and 71% and for the exercise ECG were 72% and 71%, respectively. The development of new mitral regurgitation on Doppler color flow imaging (n = 4) improved sensitivity to 81% without loss of specificity.Inducible asynergy or new mitral regurgitation was observed in 6 (50%) of 12 patients with single-, 6 (60%) of 10 with double-and 12 (86%) of 14 with triple-vessel disease. The site of transient asynergy provided additional localizing information. Exercise duration and time to diagnostic ST segment shift were shorter in patients with coronary artery disease with versus those without echocardiographic evidence of ischemia (both p < 0.05). Side effects during dobutamine infusion were mild and short-lived.Dobutamine stress echocardiography is well tolerated, is useful for detection and assessment of coronary artery disease and is applicable to patients unable to exercise

General and Specific Displacement Effects of Police Crackdowns: Criminal Events and "Local" Criminals

Geographically focused police crackdowns have widely diffused amongst larger American police departments in the past decade and have been recently cited in a Police Executive Research Forum survey as the most commonly used tactic to combat violent crime. Evidence from a number of randomized control trials, systematic reviews, and meta-analyses suggests that these interventions have the ability to reduce crime without displacing it to nearby locations. However, virtually every study of crime displacement in response to a geographically concentrated police intervention focuses on small buffer zones immediately surrounding the intervention location. While crime may not displace just around the corner, to date, few studies have tested displacement beyond this limited geographic constraint. During the summer of 2011 the Metropolitan Police Department of Washington D.C. implemented a geographically focused arrest-driven police crackdown called the Summer Crime Initiative (SCI). The current work aims to examine the impact of the SCI on the volume and placement of robbery through a quasi-experimental research design. By developing a theoretically informed framework, a broader set of hypotheses regarding local and non-local crime displacement are tested. The results of this study confirm prior research on crime displacement. Despite reductions in robbery, there is no evidence that these offenses or offenders were displaced within or beyond two blocks of the intervention sites

Piezoelectric actuator with traveling wave waveguide

A novel design of traveling wave piezoelectric actuator with a special waveguide is investigated in the paper. Actuator consists of cylinder type waveguide and piezo ceramic ring. Waveguide has conical hole inside. Such configuration of the waveguide allows increasing amplitudes of the traveling wave vibrations. Electrodes of piezoceramic ring are divided into four equal sections. Four electric signals with shifted phases by π/2 are used for the excitation. Numerical simulation was carried out to optimize the shape and dimensions of the waveguide and to maximize oscillation amplitudes at the contact surface of the waveguide. Mathematical model of the contact interface between stator and rotor was developed. A prototype piezoelectric actuator was made and experimental investigation was performed. Results of numerical and experimental investigation are discussed